Plastic pull tab adhesively secured to metal strip



June 8, 1965 J. HENCHERT 3,187,931

PLASTIC PULL TAB ADHESIVELY SECURED T0 METAL STRIP Original Filed Feb. 10, 1961 Q r 1 r ff- 4144M U (K g g m ATTORNEYS INVENTOR Jon-m HEHCHEIZT United States Patent 3,187,931 PLASTIC PULL TAB ADHESIVELY SECURED TO METAL STRIP John Henchert, Oak Park, 11]., assignor to Continental Can Company, Inc., New York, N.Y., a corporation of New York Original application Feb. 10, 1961, Ser. No. 88,473.

Divided and this application June 19, 1963, Ser. No. 289,014

3 Claims. (Cl. 22054) This application is a division of my copending application Serial No. 88,473, filed February 10, 1961.

This invention relates in general to new and useful improvements in means for opening containers, such as cans, and more particularly is directed to a novel tear strip arrangement for containers including metal can ends wherein a container may be opened by merely grasping a pull tab attached to a tear strip and removing the tear strip tothereby remove a panel of the container.

One of the primary objects of this invention is to provide a novel tear strip and pull tab combination wherein the pull tab is firmly anchored to one end of the tear strip and is of a greater width thanthe tear strip whereby the pull tab rests upon the associated container member on opposite sides of the tear strip to reinforce the tear strip at its starting end to eliminate the accidental rupture of the container member at the starting end of the tear strip. I

Another object of this invention is to provide a novel connection between a tear strip and a pull tab therefor, wherein the tear strip is in no way punctured and a good mechanical connection is obtained between the tear strip and the pull tab without the'utilization of a welding process.

A still further object of the invention is to provide a novel tear strip arrangement which includes a pull tab, the pull tab being formed of plastic and being adhesively bonded to the metal tear strip. t

This invention also proposes to provide means to facilitate the starting of the'tearing of a tear strip from the adjacent metal whereby the tear strip is provided with a generally semi-circular end portion which is scored more deeply than side edge portions of the tear strip, whereby a lesser starting force is required to rupture the tear strip along the score lines.

With the above and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claims and the several views illustrated in the accompanying drawings.

In the drawings:

FIGURE 1 is a perspective view of an upper portion of a can having a metal can end which is provided with a tear strip and pull tab in accordance with this invention.

FIGURE 2 is a perspective view similar to FIGURE 1 and shows the tear strip partially removed.

FIGURE 3 is an enlarged fragmentary perspective view showing further the general details of the tear strip and pull tab combination.

FIGURE 4 is an enlarged fragmentary vertical sectional view taken along the line 44 of FIGURE 3, and

shows the specific detailsof the connection between the pull tab and the tear strip.

FIGURE 5 is an enlarged fragmentary transverse vertical sectional view taken along the line 5--5 of FIGURE 3 and shows further the details of the connectionbetween the pull tab and tear strip, including the fact that the pull tab overlies the metal can end on opposite sides of the tear strip to prevent the accidental rupturing of the can end along the outline of the tear strip by a downward pressure.

MIC f FIGURE 6 is a fragmentary plan view showing the general outline of the tear strip at the starting end thereof and the formation of the score lines defining the same.

FIGURE 7 is an enlarged fragmentary vertical sectional view taken along the line 77 of FIGURE 6, and shows the specific arrangement of the scores in the various portions of the metal can end along the outline of the tear strip. 7

Reference is first made to FIGURES l, 2 and 3, wherein there is illustrated a conventional type of can which is generally referred to by the numeral 20, and which includes a can body 21 and a can end 22. The can end 22 is preferably formed of a light gauge metal, and it is desirable that the metal be easily rupturable. As a result, normally the can end 22 will be formed of aluminum, although the usual metals employed in the making of the can ends may be utilized. The can end 22 is secured to the can body 21 by a conventional seam 23. The can 2t) is illustrated and described only to set forth one environment of the invention. The present invention is not restricted to cans, but may be used in all types of containers, etc., where it is desired to remove a portion thereof without utilizing any opening equipment, such as a can opener in the case of a can.

Reference is now made to FIGURE 3 in particular, wherein the can end 22 is illustrated as having a circumferential tear strip 24 which is defined by a pair of score lines 25, 26 with the score line 25 being disposed outermost and being disposed adjacent the seam 23 so that when the tear strip 24 is removed, substantially the entire can end 22 within the seam 23 will be removed. The score lines 25, 26 are disposed generally in concentric relation for the most part of their lengths and the score line 26 generally defines an inner panel 27.

The' starting end of the tear strip 24, as is clearly shown in FIGURE 3, is provided with a pull tab, generally referred to by the numeral 28, to facilitate the tearing of the tear strip 24 from the can end 22. It is to be observed from FIGURES 4 and 5 that the pull tab 28 is formed of a resilient deformable plastic. The tear strip 24 is provided with an imperforate starting end 29 which is coated with a suitable thermoplastic or thermosetting adhesive 30. The adhesive 30 is utilized in the securement of the pull tab 28 to the starting end 29 of the tear strip 24.

The pull tab 28, as is best shown in FIGURE 4, is of an elongated configuration and includes a body portion 31 which is provided at one end thereof with a relatively large downwardly extending projection 32 which directly overlies the starting end 29 of the tear strip 24 and is fixedly secured thereto by means of the adhesive 39.

The body portion 31 is intended to be grasped in a manner to exert a tear strip tearing and removal force on the tear strip 24. In order to facilitate this, the body portion 31 is provided adjacent the end thereof remote from the projection 32 with an upper rib 33 and a lower rib 34. The ribs 33 and 34 extend transversely of the body portion 31 and are preferably in alignment. The rib 34 is of a thickness to rest upon the uppersurface of the can end 22 in the normal position of the pull tab 28.

particularly the projection 32 thereof, is of asuflicient It is to be noted from FIGURE 5 that the pull tab 28,

strips at the starting end of each tear strip, are shown. For identification purposes only, the partial can end illustrated in FIGURE 6 will be considered to be the can end 22, and the tear strip, the tear strip 24. As was previously described, the tear strip 24 is defined by a pair of score lines 25,26. As is best illustrated in FIG- URE.7, these score lines 25, 26 are relatively shallow. The score lines 25 and 26 will preferably be of a depth so that theremaining metal to'be torn in the removal of the tear strip 24 will have a thickness of 0.003 inch. The ends of the score lines 25, 26 are connected together by a generally semi-circular score line 102 which has a greater base width and is' of a greater depth, as is best illustrated in FIGURES 6 and 7. The depth of the score line 102 will be such that in most instances, the remaining thickness of metal to be torn will range between 0.001 inch and 0.0015 inch. By making the score line 102 much deeper than the score lines 25, 26, it will be readily apparent that a sharp upward pull on the starting end of the tear strip 24 by means of the pull tab 28 will result in the rupturing of the metal of the can end 22 along the score line 102. Once the initial rupturing has been accomplished, the 'tear strip 24 may be removed by continuously exerting an upward pull thereon with the tear strip 24 being torn from the can end 22 along the tear lines 25, 26. V

The advantage of the relatively deep score line 102 coupled with the supporting feature of the individual pull tab is obvious. Applicant has made the initially torn portion of the can end of sufficient weakness to facilitate the easeof tearing the starting end of the tear strip therefrom. On the other hand, by making each pull tab of a sufficient width to engage the can end outwardly of the tear strip, the tear strip is prevented from deflecting inwardly due to any accidental force exerted thereon, whereby the can 20 would be opened prematurely,

From the foregoing, it will be seen that novel and advantageous provision has been made for carrying out the desired end. However, attention is again dir ected to thefact that variations may be made in the examples I claim:

1. In a container, a tear strip assembly for facilitating the opening of a container without the use of any additional device, said tear strip assembly being formed in a panel of said container and comprising a tear strip forming an integral part of said container panel, said tear strip being primarily defined by two spaced score lines in said panel and including a starting end, a pull member overlying said tear strip starting end for facilitating the manual tearing of said tear strip from said container panel to effect. the opening of said container, a permanent adhesive bond joining the tear strip starting end to the pull member, said two score lines being joined by a starting score line portion at least partially defining said tear strip startingend, said starting score line por tion being of a greater depth than said two score lines and presenting a line of least resistance to rupture to facilitate the. starting of the tearing of said tear strip from said container panel, said pull member having an attaching portion and a grip. portion with at least said attaching portion being rigid, and said pull member attaching portion protectively overlying said starting end portion and being adapted to rest on said container panel outwardly of said tear strip to resist accidental rupture of said of the invention disclosed herein without departing from the spirit and scope of the'invention, as defined in the appended claims.

container panel along said starting score line portion by an accidental inward displacement of said tear strip starting end. 1

2. The tear strip assembly of claim 1 wherein said grip portion extends from an upper part of said attaching portion and is spaced above said panel to facilitate the initial grippingof said grip portion.

3. The tear strip assembly of claim 2 wherein said grip portion has transverse ribs extending thereacross and projecting above and-below said grip portion, and at least one of said ribs resting on said panel to maintain said grip portion in spaced relation to said panel.

References Cited by the Examiner UNITED STATES PATENTS 2,870,935 1/59-H0ughtelling 22053 2,978,140 4/61' Walsh. 3,083,858 4/63 Biedenstein 22O27 THERON E.CONDON, Primary Examiner. V 

1. IN A CONTAINER, A TEAR STRIP ASSEMBLY FOR FACILITATING THE OPENING OF A CONTAINER WITHOUT THE USE OF ANY ADDITIONAL DEVICE, SAID TEAR STRIP ASSEMBLY BEING FORMED IN A PANEL OF SAID CONTAINER AND COMPRISING A TEAR STRIP FORMING AN INTEGRAL PART OF SAID CONTAINER PANEL, SAID TEAR STRIP BEING PRIMARILY DEFINED BY TWO SPACED SCORE LINES IN SAID PANEL AND INCLUDING A STARTING END, A PULL MEMBER OVERLYING SAID TEAR STRIP STARTING END FOR FACILITATING THE MANUAL TEARING OF SAID TEAR STRIP FROM SAID CONTAINER PANEL TO EFFECT THE OPENING OF SAID CONTAINER, A PERMANENT ADHESIVE BOND JOINING THE TEAR STRIP STARTING END TO THE PULL MEMBER, SAID TWO SCORE LINES BEING JOINED BY A STARTING SCORE LINE PORTION AT LEAST PARTIALLY DEFINING SAID TEAR STRIP STARTING END, SAID STARTING SCORE LINE PORTION BEING OF A GREATER DEPTH THAN SAID TWO SCORE LINES AND PRESENTING A LINE OF LEAST RESISTANCE TO RUPTURE TO 